HT155 - HT157
EN - 24
5.2.
NOISE ANALYSIS IN 1/1 AND 1/3 OCTAVE BAND (HT157 ONLY)
Further to the statistic analysis, the instrument HT157 allows carrying out accurate
measurements of the noise spectrum by using internal octave-band (1/1) and third-octave-
band (1/3) filters
5.2.1. INITIAL
OPERATIONS
1. Turn on the instrument by pressing the “
” key. The screen for the selection of the
analysis type is shown on the display for approximately 5s (see Fig. 22)
Fig. 22: Initial screens for analysis in 1/1 and 1/3 octave band
2. Use the “
” or “
” keys to select the item “1/1 OCT Analyzer (00202)” and press “
”
to activate the octave band analysis (1/1) or the item “1/3 OCT Analyzer (00303)” and
press “
” to activate the third-octave band analysis (1/3). The instrument shows the
main menu consisting of 6 icons on the display
3. Select the relevant icon and press “
” to enter the specific menu:
List
the instrument shows, in numerical form, the sound pressure level for each
central band frequency in the range 16Hz
16kHz (1/1 analysis) and in the range
12.5Hz
16kHz (1/3 analysis) and the equivalent levels weighted A, C and Z
Graph
the instrument shows the histograms of the 1/1 and 1/3 analyses
Total
the instrument shows the whole of the data of the spectrum analysis
Data
Section which contains the data of the recordings saved with the instrument
(see §)
Setup
allows accessing the instrument’s programming menu (see § 4.6)
Calibrate
section in which it is possible to make the initial calibration by using the
provided portable calibrator HT151 (see § 6.1.3)
4. The indication next to the icon “
:XXX” in the right-hand top part of the display
indicates the number of the group of the datum which can be saved in the instrument’s
memory
Summary of Contents for HT155
Page 1: ... Copyright HT ITALIA 2011 Release EN 1 02 28 12 2011 HT155 HT157 User manual ...
Page 2: ......
Page 62: ...HT155 HT157 EN 60 12 APPENDIXES 12 1 APPENDIX 1 FREQUENCY WEIGHTING CHARACTERISTICS ...
Page 63: ...HT155 HT157 EN 61 12 2 APPENDIX 2 CHARACTERISTICS OF 1 3 OCTAVE BAND FILTER ...
Page 64: ...HT155 HT157 EN 62 ...
Page 65: ...HT155 HT157 EN 63 ...
Page 67: ...HT155 HT157 EN 65 12 4 APPENDIX 4 CHARACTERISTICS OF 4HZ HIGH PASS DIGITAL FILTER ...